This invention relates to slip joint seal assemblies having elastomeric sealing bodies. More particularly, the invention relates to the effectiveness of such sealing bodies for controlling the flows of lubricant during relubrication of special lubrication chambers or cavities associated with such seal assemblies.
Prior art seal assemblies of the relubrication variety have been inadequate to effectively seal against escape of lubricant during relubrication. In seal assemblies which utilize sealing lips for the purpose of restraining flow of lubricant during relubrication, prior art lips have maintained constant contact with the shaft sealing surface and have become prematurely worn. In addition, such sealing members have occasionally given rise to phenomena which render the primary sealing of the assembly less effective. For example, one such assembly actually experiences a wobbling back-and-forth motion of the elastomeric sealing body along the shaft as the splined members are extended and retracted with respect to one another. This action allows contamination to enter into the otherwise protected internal spline region.
The problem would probably be exascerbated by the use of dual primary sealing lips, which could result in extra forces on the primary sealing lips. An improved elastomeric body seal assembly is needed over the assemblies available in the prior art, particularly in situations where dual primary lips will be utilized.